By "glissando" in organ playing is meant the technique of a quick sliding up or down, note to note, of a single finger, a thumb, a single hand, or both hands together; this may be done at the organ either diatonically (by scale degrees) or chromatically (in half steps), and, when correctly performed, can be extremely effective in making the new organist's playing sound smooth, or ear-catching and flowing.
This is a subject best taught at the keys; this posting therefore is an attempt to codify in words how the various types of glissandos are executed.
Any finger or either thumb can be trained to "slide" to any adjacent key to effect an uninterrupted legato of a single moving line; this so-called "finger glissando" and "thumb glissando" along with substitution, are employed in piano playing to a much less extent, if at all, due to the presence of a damper pedal which permits notes to continue sounding when the fingers move to different keys; these however are all non-negotiable, essential points of organ technique.
The question of which notes to play as well as how many is most important; knowing ALL the scales and chords (major, minor, 7ths, etc.) and the chromatic scale intimately will make the correct, natural fingering and the working out of all forms of glissando seem second nature.
There has always been some slight difference of opinion among teachers regarding the fingering of scales and chords, and the construction of a person's hands should serve as the guide here.
For persons with average size hands the traditional teaching is for the 3rd (middle) finger to always be on the black keys when fingering the chromatic scale ascending or descending (photo); the middle finger is the longest, strongest finger and can be trained to work very quickly with the thumb.
When playing pieces the thumb should be kept on the white keys whenever possible but at times it will be necessary to use it on the black keys.
The touch used with any form of glissando is ALWAYS legato.
When a very rapid, all-white-key, note-at-a-time glissando is to be performed on the manuals ascending or descending, the part of the hand which contacts the keys can be either the side of the thumb at the thumbnail or the tip of the nail of the index finger; the ideal here would be to have just one white key sounding at a time, but the starting note and destination note may be either white or black.
Some performers, in playing a very rapid ascending all-white key glissando with the right hand, prefer to use the medial side of the right little ("pinky") finger; less commonly, in any home key, a very rapid ascending all-white-key glissando can be effected by sliding the whole thenar eminence of the left hand (the bulge which joins the thumb with the palm of the hand) upward along the edges of adjacent white keys; this causes more than one key to sound at the same time, the dissonance being maintained all the way up to the top until the high destination note(s) or chord is reached.
This it taken commonly by the left hand on the manual below where the right hand is playing, and, if not overdone, can make for a spectacular ending with the full organ.
For extended range, single-note glissandos using the right hand, the side of the right thumb is typically used if ascending, and if descending with the right hand (which is less common) the right wrist would be rotated inward (pronated) slightly and the tip of the nail of the right index finger, which remains curved throughout, would contact the edges of adjacent white keys all the way down.
For extended range, single-note glissandos using the left hand, the side of the left thumb would be used in descending, and if ascending the left hand would be rotated inward (pronated) slightly and the tip of the nail of the left index finger, which remains curved throughout, would contact the edges of adjacent white keys all the way up.
This type of glissando is very commonly employed as an upward sweep on a separate manual with a tuned percussion stop such as a celesta or harp drawn, the effect meant to imitate the upward chromatic glide of the orchestral harp; meanwhile, while the left hand is executing the glissando, the right hand is doing something else on a manual below.
There is also a type of ascending multiple-note all-white-key glissando consisting of a major triad chord in close harmony position where the destination chord is of the same fingered position as the starting chord; freezing the fingers in the position of the first chord and keeping them in that same position as the entire hand glides upward along the white keys simplifies its execution; with this technique the right wrist is rotated outward (supinated) slightly and the fingers of the right hand are curved.
Should the destination chord be of a different fingered position than that of the starting chord, the fingers can be left in the starting fingered position until the just before the end of the glissando.
When playing dramatic song arrangements which have a big finish it's always a good idea to save an extra inch of swell pedal opening for the very last; should we want an extra "kicker" after the pedal is fully open and the final chord is being held high by the right hand, one might then draw the biggest chorus reed stops on a higher manual and execute the final left hand chord on that manual by starting on the same chord a chromatic half step higher, then slide the left fingers and thumb downward by a half-step as quickly as possible.
This technique of final chord glissando also works best when the final chord lands on mostly, if not all, white keys.
On the pedals the all-white-key glissando is almost always performed descending and with the inner surface of the left toe; the "feel" is that of using the big toe of the left foot to slide downward until the destination pedal note is reached; here again, the starting note and destination note may be either white or black.
Chromatic glissandos are performed on the manuals only and may be either single note or multiple-note.
When traveling between 2 different single melody notes widely separated, the insertion of too many glissando notes will make it obvious that the performer is striving for the glissando effect; if we find that we're trying to include too many notes between the starting note and destination note to keep from overdoing it or simply to stay in rhythm, we might glissando only through the first, second, or third chromatic note and drop the remainder.
If the harmony at the starting melody note moves to a different harmony at the destination note, the general tonal trend also must be considered; in each case the notes in the glissando will need to incorporate a semitone which moves the harmony into the destination chord.
The video of "I'll Be Home For Christmas" posted on this web site demonstrates how glissandos can be incorporated into a song to make it more flowing and attention-getting [See menu bar, Videos].
Multiple-note chromatic glissandos are of many different types; some are executed using both hands playing in 3-note close harmony position, some are in open harmony position; those in open harmony might include a chromatic run of 2 notes, one in each hand, or maybe only one note in the left hand running chromatically; the right hand also might play the top melody note and another note at the interval of a minor 3rd or minor 6th below it, then move the melody note after a glissando switches the interval to a minor 6th or minor 3rd, respectively, using just a single hand.
In the glissando for 2 hands the moving chromatic lines are kept a minor 3rd or a minor 6th apart; this means that one of the hands might have to be started first to establish this intervallic distance -- and, if one hand arrives where it needs to be in the destination chord just ahead of the other hand it may have to be held through one note change to allow the other hand to catch up to where the all notes in the destination chord can be sounded at the same time.
Whatever kind of chromatic multiple-note glissando in open harmony position is used, the top (melody) note typically is held through the first few notes of the chromatic run and more commonly takes no part of the run itself (although it could if, for example, in descending the intervallic distance between the falling melody note in the right hand sounds at a minor 10th above the falling left hand note and the destination chord is also in open harmony position).
In the coda for full organ which incorporates an ascending double note glissando with both hands spaced a minor 3rd apart over 3 octaves of range and which ends on a root position tonic major chord, such a finish is spectacular but it too must not be overdone.
To keep the final right hand chord from sounding too thin in the top octave plenty of 16-foot manual tone needs to be drawn when executing this kind of glissando.
It starts first in the right hand on a single dominant note in the bottom of the tenor octave and as the run climbs upward with the next note the left hand enters a minor 3rd below it and slavishly follows it upward, always maintaining its same intervallic distance; when the right hand note reaches the dominant note in the top octave it stays there while the left hand plays both the mediant note and the tonic note to form the tonic chord in root position.
The holding of a dominant pedal point while this type of glissando is climbing chromatically will be found advantageous in that it provides a tonal anchor amidst all the fast-paced chromatic sweep going on above it.
Ending on a root position tonic major triad happens to work perfectly with this because the 3rd and 5th scale degrees which go into forming the root position of this chord are themselves a minor 3rd apart; as both hands arrive on these 2 notes in the top octave all the left hand has to do is add the 3rd note (the 1st scale degree) to form a completed triad.
Mastery of this technique is not all that difficult, but it does require concentration and slow practice of the ascending chromatic scale, hands separate at first, then both hands together, gradually increasing the speed so that it can be played very quickly, accurately, and effortlessly; it's critically important that the hands maintain the interval of a minor 3rd at every point along the sweep (this is realized more by how it should "feel" than by trying to watch the movement of each individual key -- an impossible task); with steady practice this will seem to fall into place by itself.
A demonstration of this may be viewed in the video of "Jingle Bells" posted on this web site [See menu bar, Videos].
A valuable reference work which has a whole chapter devoted to the glissando is the out-of-print plastic comb-bound book "A Study In Theatre Organ Style" by legendary theatre organist Don Baker published by Peer International Corporation in 1968; this reference comes highly recommended -- if the new organist could have only one volume on theatre organ playing with sample arrangements included, this would be it.